Large capacity mining draglines subject a dragline bucket to enormous forces and loads. The ropes (also referred to as “cables”) are employed in draglines to control the various movements of the bucket, and accordingly experience extreme and rapid wear, especially at the sheaves in components of the dragline. For example, hoist ropes may need to be replaced every 3-6 months, drag ropes every 1-3 months and dump ropes every 1-2 weeks. Rope replacement is time consuming, with “downtime” of the dragline representing a significant cost in mining operations.
Minimizing the rope changeover time and improving rope integrity so as to decrease the incidence of ferrule-to-rope failure can each contribute to downtime reduction and improved operating cost and efficiency.
It is known to connect ferrules to wire ropes by a swaging method or a jaw-pressing method. Such methods have been observed to provide sufficient securement of the ferrule to the wire rope for a number of applications in which wire ropes may be employed. However, such methods are unlikely to provide sufficient securement of a ferrule to a wire rope for dragline conditions.
GB 1,369,211 discloses a ferrule on a wire rope. The ferrule can be secured to the wire rope by swaging or by a type of die-pressing that imparts a shaped profile to the ferrule. In other words, the ferrule is die-pressed by a die set that is laterally directed to press the shaped profile onto the ferrule. The profiling of the ferrule necessitates a lateral pressing, hence the method of GB 1,369,211 is not concerned with nor able to address the securement requirements of a ferrule to a dragline rope.
GB 2,113,732 discloses a connecting device for the end of a wire rope to enable the end to be connected to a hook or bolt. A ferrule is secured to the wire rope by a swaging operation. The secured ferrule retains a proximal end of a connecting coupling onto the end of the rope, with a distal end of the coupling being internally threaded for receiving therein an externally threaded shank of the hook or bolt. Again, the method of GB 2,113,732 is not concerned with addressing the securement requirements of a ferrule to a dragline rope.
The above references to the background and prior art do not constitute an admission that such art forms a part of the common and/or general knowledge of a person of ordinary skill in the art. The above references are also not intended to limit the application of the method disclosed herein.